Abradant supplying means



Dec. 22, 1953 J. J. HUNT ABRADgXNT SUPPLYING MEANS Filed Sept. 13, 1952 INVENTOR. JOHN J. HUNT ATTORNEY Patented Dec. 22, 1953 warren STATES rarest oasis 2,663,127 ABRADANT- SUPPLYI-NG MEANS John J. Hunt, Irondequoit, N. Y., assignor to Bausch & Lomb Optical Company, Rochester, N. Y., a corporation of New York Application September 13, 1952, Serial N 0. 309305 8 Claims. 01. 51 2s3) This invention relates to improvements in. lens polishing apparatus and the like andmore. parand the work. As the movement of the polishing tool continues, the friction between it and the work gradually increases as the abrasive mix.- ture evaporates and becomes exhausted. important that a fresh application otthe abrasive mixture be made at the proper time. so as to avoid excessivefriction and resulting high temperatures and other conditions which would be detrimental to the lenses or objectswhich are being polished. On the other hand, it is. also important that a certain amount of. friction should exist .between the polishing tool and the work in. order that the polishing operation will be efiiciently accomplished. In polishing lenses, for example, ona large scale, it is customary for one operator to attend to a large number of polishing units and make periodical applications of rouge and water. Sucha procedure makes it impossible; from a practical standpoint; to supply each polishing unit with an application. of rouge and Water at the proper time in. order to. insure themost efiicient operation.

Likewise, in the grinding of lenses,.an abrasive such as emery and water isv applied periodically to the work and it is also important that the abrasive be applied at the proper time: in order to insure the desired results and efficiencysin operation. Under the prevailing practice the grinding abrasive, such as emery and water, is also applied to the abrading tool by the operator who must attend'to a large number of grinding units, thereby making. it practically impossible to, apply the .abrasive so as to insure the greatest grinding efiiciency for each individual unit;

By means of my invention, however, I amable tov overcome. the difiiculties due to improper applications of abrasive and provide means for controlling and applying the abrasive so as to insure the greatest eiiiciency of; operation, as willhereinafterbe more fully described.

In operating lens polishing. machines, for example, the maximum efficiency is obtained when the. fluid. abradant is; applied periodically tothe WQlki. .Devicesior. making such. periodic. applia- It. is

2 cations. ofabradant. automatically have been proposed. In such devices the automatic application of abradant is accomplished by placing valves; in the abradant system which are actuated. periodically to. cut cit; the flow of abradant. Heat, friction and various other phenomenon of the grinding surface of the tool. have been em ployed to actuate. the valves. But generally when the flow had been shut oil, the rouge in the. abradant mixture settled out rapidly and clogged the circulating system. The settled rouge became so. hard thatitwas often necessary to drill thev pipes out to clear the system. Still, a continuous: flow of abradant onto the work surface was not advisable, as little or no abrading action could: take: place when the work surfaces were: continually lubricated.

Therefore, it. isan object of this invention to provide an automatic means for supplying an intermittent flow of abradant to a work surface from a continuously flowing stream of fluid abradant. More specifically, it is an object of this invention to provide an. 'abradant supply mechanism that is fully automatic in operation. Another object of this. invention is to provide a mechanism. that maintains a continuous stream of abradant in'the system. A further object of this invention is to provide a mechanism that has ameans for supplying an intermittent stream of abradantto a work surface.

Further objects and advantages of. the present invention will appear from the following descriptiontaken in connection with the accompanying drawing in which:

Fig. 1 is a general perspective view of a pre ferred: form of my'invention incorporated in a polishingmachine, some parts being broken away and shown. in section,

Fig.2 is an.- enlargedside. elevation of certain partsof the structure shown in Fig. 1 with some parts broken away. and shown in section, and

Fig. 3.is a diagrammaticside view of a modification of myinvention' with some. parts shown in section...

In one form of my invention, such as shown in Figs. 1 and 2, a. grinding or polishing apparatus H3 is principally. composed of an oscillating head II, a rotatable lower member ii, an

abradant. nozzle. 25, and an abradantv directing trou h 27; V Y

The head. M- is mounted to oscillate about pivot lz'through link :3. The splash shields H3 and it areeiastened to oscillate. with link; It and'head l;l.. Overlappingtheshield i6 isashield it which isinountcd to; oscillate with an adjoining head,

not shown. Extending downwardly from the head I is the spindle holder L! which removably retains the retractable power operated spindle H. The lever l8 on the head controls the mechanism for raising or lowering said spindle Said spindle ll acts through a universal coupling 44 to control a lens holding block 20. Element 2!] is sometimes referred to as an upper member, it should be understood that this upper member could be a grinding tool without departing from the spirit of this invention. The lens holding block 20 has a lens 23 secured therein with one face exposed for grinding. Disposed below the block 20 is a tool 2| having an abrading surface 22 2| is sometimes referred to as a lower'member, it should be understood that a lens block could in contact with lens 23. Element be substituted for the tool without departing from the scope of this invention.

A supporting shield 36 disposed above the tool is fastened by nuts 33' to bracket arms 32 and 33 which in turn are fastened by set screws 34 to anchor block 35. The anchor block 35 is fastened to the spindle holder I?) by any suitable means. Therefore, when the spindle holder is oscillated about pivot l2, the shield 36 and trough 21 are also oscillated. Likewise, when spindle holder I9 is raised by lever |8, the shield 35 and trough 21 are also raised. The trough 21 can be of any desired shape or construction, such as the inverted V-shaped member shown, having an upstanding wall 3| at the apex dividing the trough into two downwardly directed segments 28 and 29. The one segment 29 of the trough projects through the aperture 31 in the shield 3t and is fastened therein by brackets 38 and screws 39. The trough 21 is disposed in a plane above the contact plane of the tool 2| and lens 23. A stream of abradant flows from a nozzle 25 into the trough. The segment 28 directs the abradant that flows to the left of wall 3| onto the tool, while segment 29 directs the abradant that flows to the right of wall 3| into the overflow channel 26.

A wall 24 of the machine has nozzle 25 lying in a plane above the plane of the trough to eject a continuous stream of abradant material toward the trough. An overflow channel 26 is located below the tool 2| and lens 23 to catch the surplus abradant that flows from the tool or from the trough. The nozzle 25 is part of a circulating system, not fullyshown, that supplies a continuous stream of abradant to the abrading apparatus.

Another embodiment of the invention is shown in Fig. 3 wherein a splash shield I4 is mounted to pivot with head I I about pivot I2 and splash shield I5 is mounted to pivot with head about pivot I2. An inverted V-shaped trough 40 is divided into two segments by an upstanding wall 43. One segment of the trough projects over tool 2| and the other segment projects over tool 2|. The trough G0 is supported by pivot 4| on splash shield M and by pivot 42 on splash shield l5 so as to oscillate back and forth with the oscillating heads H and H. Abradant flow nozzle 25 is fixed to a support and projects over the trough 40. When the machine is in operation, a continuous stream of abradant flows from nozzle 25' toward the trough 40 and it is directed intermittently and successively onto the tools 2| and 2| by the movement of the wall from one side of the stream of abrasive to the other.

In the operation of the embodiment shown in Figs. 1 and 2, the lens 23 and tool 2| are oscilabrading of the lens will result.

lated and rotated relative to each other. As the trough 2'! is moved back and forth laterally by head relative to the nozzle 25, the wall 3| is moved through the stream of abradant whereby abradant flows alternately on opposite sides of the wall. In this manner, the tool receives abradant intermittently from that portion of thetrough nearest the tool. During the interval when no abradant flows onto the tool, the friction between the tool and the lens will increase and an effective In this form of the invention, the amount of abradant directed to the tool for each reciprocation of the trough may be changed by adjusting the trough closer to or farther from the spindle holder It). In this way, the wall 3| stays longer on one side of the stream than on the other, to thereby increase or decrease the amount of abradant flowing to the tool.

In the modification shown in Fig. 3, an equal amount of abrasive compound will be supplied to each tool 2|, 2|" by adjusting wall 53 to oscil late equally on opposite sides of continuous flow nozzle 25. As the trough 40 oscillates, the flow will first be conducted by one part of the trough to the one tool and then by the other part of the trough to the other tool. In this manner, equal amounts of abradant are fed to each set of tools and lens blanks to permit equal abrading of each lens blank.

It has been shown that a continuous stream of abradant material can be maintained without a continuous lubrication of the lens surface. By maintaining a continuous stream of abradant mixture, the rouge or solid material in the mixture does not settle out and clog the circulating system, thus overcoming one of the chief disadvantages of the prior devices. The intermittent flow of compound to the tool permits more rapid abrading of the lenses.

Although only certain forms of my invention have been shown and described in detail, it will be understood that numerous modifications, changes, substitutions and rearrangement of parts may be made without departing from the spirit of the invention as claimed in the appended claims.

I claim:

1. In a lens grinding apparatus including a relatively movable grinding tool and lens holder, a nozzle lying in a plane above the tool for ejecting a continuous stream of abradant material, the combination of means for intermittently directing the stream of abradant material from said nozzle onto said tool, said means comprising a movable trough lying in a plane located between the nozzle and tool, and means for moving the trough to cause a portion thereof to pass through the stream whereby the abradant material is intermittently directed onto said tool.

2. In a lens grinding apparatus having a continuous stream of abradant fed toward the contacting surface of the lens and tool elements that are being rotated and oscillated relative to each other, the combination of means for providing intermittent flow of said abradant to said tool, said means including a movable trough positioned partially over said tool and in the path of the abradant stream, a wall across said trough, means for imparting oscillating motion to said trough to alternately move the wall to opposite sides of. the stream whereby the abradant will be intermittently fed onto said tool.

3. A lens polishing apparatus using a solid suspended in liquid as an abradant comprising a lower rotatable member, an oscillatively mounted upper member contacting said lower member, a nozzle lying in a plane above the lower member for ejecting a continuous stream of abradant material, means for intermittently directing the stream of abradant material from said nozzle onto said lower member, said means comprising a movable trough lying in a plane located between the nozzle and the lower member, and means for moving the trough to cause a portion thereof to pass through the stream whereby the abradant material is intermittently directed onto said tool.

4. A lens polishing apparatus comprising. a lower rotatable member, an oscillatively mounted upper member contacting said lower member, a nozzle lying in a plane above the lower member for ejecting a continuous stream of abradant material, a trough mounted to oscillate with the upper member and lying in a plane located between the nozzle and the lower member, a segment of said trough intercepting thestream during a part of each oscillation of said upper member and said. trough, said segment directing said intercepted stream onto the lower member, and

. means for oscillating the upper member and the through whereby the abradant material is directed intermittently onto the lower member.

5. A lens polishing machine having a relatively movable polishing tool and lens holding element comprising a nozzle lying in a plane above the tool for supplying a continuous stream of abradant, means for intermittently directing said abradant to said tool, said means comprising an inverted V-shaped trough for receiving said abradant from said nozzle, an upstanding wall at the apex of and integral with said trough for dividing said trough into two downwardly directed segments, one segment directing abradant onto said tool, and means for producing relative motion between said trough and said nozzle whereby abradant is alternately directed on opposite sides of the wall to provide intermittent flow onto the tool.

6. A lens polishing apparatus using a solid suspended in liquid as an abradant comprising a lower rotatable member, an oscillatively mounted upper member contacting said lower member, a supporting'shield secured to said upper member, a trough secured tosaid shield, a wall dividing said trough into two segments, one segment extending through said shield and lying in a, plane above the lower member, a nozzle directing a continuous stream of abradant into said trough and means for simultaneously oscillating the upper member and the trough to alternately move the Wall to opposite sides of the stream whereby abradant is directed intermittently into said segment of the trough and onto the lower member.

'7. A lens grinding apparatus of the character described comprising two spaced rotatable grinding tools, two spaced oscillatively mounted work holding members in operative relation with said grinding tools, an inverted V-shaped trough having an upstanding wall at an apex for dividing said trough into two downwardly directed segments, each segment terminating in a plane above said tools, a nozzle in a plane above the trough directing a continuous stream of abradant into said trough, said trough being mounted to oscillate with said work holding members to move said wall from one side of the stream of abradant to the other whereby the continuous stream of abradant is directed intermittently onto the respective grinding tools.

8. A lens grinding apparatus of the character described comprising a rotatable tool, an oscillatively mounted head holding a lens in grinding contact with said tool, a nozzle disposed in a plane above the tool for supplying a continuous stream of abradant, a trough divided into two segments by an upstanding wall, said trough being disposed in the stream of abradant and having one segment directing abradant onto said tool, a splash shield carried by the head, said trough being mounted on the-shield and having a portion projecting through an opening in the shield, said trough being oscillated with said head to alternately move the wall to opposite sides of the stream whereby an intermittent stream of abradant will be directed onto the tool.

JOHN J. HUNT.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,037,851 Beam Sept. 10, 1912 1,063,434 Hachneister June 3, 1913 1,619,344 Hill Mar. 1, 1927 1,800,743 Morris Apr. 14, 1931 2,083,773 Burroughs June 15, 1937 FOREIGN PATENTS Number Country Date 668,226 Germany Nov. 3, 1936 

